How many ventricles are there and what are they?
What hole connects the lateral ventricle to the third ventricle?
the interventricular foramen = foramen of Monroe
What are the three foramen in the 4th ventricle?
1 median foramen = foramen of Magendie
2 lateral foramen = foramen of Luschka
Where is the suprasellar cistern located?
above the sella turcica
What percentage of the CSF is made by the choroid plexus and what percent is extrachoroidal?
90% and 10%
What ventriccle does NOT have a choroid plexus?
the cerebral aqueduct
What are the two layers of cells in the choroid plexus?
luminal surface = ependymal cells with tight junctions preventing diffusion of circulatin blood components from passing into the ventricles
then capillary endothelium that forms the core of the plexus consisting of a fenestrated endothelium
CSF formation is an ___ transport process requiring ATP
What is a normal number of cells in CSF (lymphocytes/monocytes)
protein: 15-45 mg/dL
glucose: 60-80 mg/dL
What should the opening lumbar pressure be for the CSF in lateral recumbent position? sitting?
lateral = 50-200 mm H2O
sitting: 200-300 mm H2O
About how much total CSF is located in the ventricles and subarachnoid space?
How many times is the CSF renews daily?
Describe the general path of CSF through formation to recycling?
1. lateral ventricle - formed by choroid plexus
2. passes through foramen of monroe into third ventricle
3. passes through cerebral aqueduct to fourth ventricle
4. Can either pass through the median foramen or lateral foramens into the subarachnoid space
5. moves thorugh cisterns, down aroudn the spinal cord, brain stem, through tentorial notch, up and over the superior sagital sinus, etc.
resorbed back into venous system through arachnoic granulations
Why will CSF leave the ventricular system to enter the dural sinuses?
higher hydrostatic pressure of CSF compared to venous blood in the dural sinuses
higher colloidal osmotic pressure of blood due to proteins
active transport too